Hydrochloric Acid → 5-(1-Hydroxyguanidin-3-yl)imino-4-methyl-7-(3-thienyl)-5,6,7,8-tetrahydroquinoline hydrochloride

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-methyl-7-(3-thienyl)-5,6,7,8-tetrahydroquinolin-5-one (243 mg), 1-amino-3-hydroxyguanidine p-toluenesulfonate (393 mg) and concentrated hydrochloric acid (0.2 ml) in ethanol (3 ml) was stirred at 90° C. (bath temperature) for 2 hours. The reaction solution was concentrated under reduced pressure, and to the residue were added ethyl acetate (30 ml), tetrahydrofuran (20 ml) and 0.2 N sodium hydroxide (20 ml). The mixture was shaken, and the separated upper layer was washed with 0.2 N sodium hydroxide (10 ml) and water (10 ml, thrice). To the upper layer was added 2 N hydrochloric acid (1 ml), and the mixture was concentrated under reduced pressure. To the residue was added ether (3 ml), and the mixture was stirred at 90° C. (bath temperature) for 2 hours and cooled to give crystals, which were filtered, washed with ethanol and dried to give 5-(1-hydroxyguanidin-3-yl)imino-4-methyl-7-(3-thienyl)-5,6,7,8-tetrahydroquinoline hydrochloride (Compound 103) (233 mg) as pale yellow crystals.

Provenance & Evidence